1. Field of the Invention
The present invention relates to a liquid refill technique of refilling a liquid into a liquid container structured to store the liquid, which is to be supplied to a liquid consuming device.
2. Description of the Related Art
In ink-jet printers, in response to detection of out-of-ink with consumption of ink stored in an ink cartridge, the used ink cartridge is generally replaced with a new ink cartridge. As ink cartridges are recycled, more active approaches for the more efficient use of resources have been demanded and discussed. One approach refills ink into the used ink cartridge. Some techniques have been proposed for ink refill in the ink cartridge as disclosed in, for example, Japanese Patent Laid-Open No. 2007-508160.
The ink refill technique disclosed in this cited reference seals an ink outlet of the ink cartridge with a plug, drills or otherwise bores a through hole in the outer wall surface of the ink cartridge, refills ink via the through hole into an ink reservoir assembly by means of an injector, and seals the through hole after the ink refill. This prior art ink refill technique expects the air remaining in the ink cartridge to be naturally discharged out via the through hole designed to have a larger diameter than the diameter of the injector during the ink refill.
The ink refill technique disclosed in the cited reference seals the ink outlet and causes the air remaining in the ink cartridge to be discharged out via the through hole during the ink refill as mentioned above. This structure interferes with the ink flowing into a pathway between the ink reservoir assembly and the ink outlet and accordingly does not attain the efficient ink refill. The ink refill technique of the cited reference is not simply applicable to ink cartridges of the complicated and advanced internal structure. For example, in an ink cartridge equipped with a sensor unit including an ink sensor that utilizes a piezoelectric element to detect the level of remaining ink, the ink flow path structure is especially complicated to avoid false detection of the ink sensor caused by migration of the air into the sensor unit. Formation of the through hole at an inadequate position may damage the functions of the ink cartridge. The complicated structure of the ink flow path has high flow resistance and may thus interfere with efficient ink refill.
This problem is not characteristic of the ink cartridge for the printer but is commonly found in diversity of liquid containers used for supplying a liquid to a liquid consuming device, for example, a liquid container for supplying a metal-containing liquid material to an injection device designed to inject the liquid material onto a semiconductor substrate and thereby form an electrode layer on the semiconductor substrate.